Geography and History 1 Key concepts is a collective work, conceived, designed and created by the Secondary Education department at Santillana, under the supervision of Teresa Grence.

WRITERS Pedro Adiego Álvaro BellónMaría Ángeles FernándezRosa LópezJavier VelillaFrancisco Javier Zabaleta

EDITOR Raquel Rubalcaba

EXECUTIVE EDITOR María Antonia Oliva

PROJECT DIRECTOR Lourdes Etxebarria

BILINGUAL PROJECT DIRECTOR Margarita España

Do not write in this book. Do all the activities in your notebook.

SEC

ON

DA

RY

1Geography and HistoryKey concepts

1. Planet Earth 4

1. The Earth and its movements 2. The representation of the Earth

2. The Earth’s relief 10

1. The Earth’s crust and the Earth’s relief 2. World relief 3. Relief formation 4. How does relief change?

3. Water 20

1. Continental water: rivers 2. Other continental waters: marine waters

4. Climate 26

1. Elements of climate 2. The Earth’s climates 3. The climate and our lives

5. Natural landscapes 34

1. Hot climates 2. Temperate zones 3. Cold zones

6. The continents 42

1. Africa and Asia 2. America and Europe 3. Oceania and Antarctica

7. The physical relief of Spain 50

1. The relief of Spain 2. Rivers in Spain 3. Spain’s natural environment

8. Prehistory 58

1. The Palaeolithic Age 2. The Neolithic Revolution 3. The Metal Age

9. Ancient Mesopotamia and Egypt 66

1. Mesopotamia: history and society 2. Mesopotamia: religion, architecture

and art 3. Ancient Egypt: history and society 4. Religion and art in Ancient Egypt

10. Ancient Greece 76

1. Origins 2. The Classical and

Hellenistic Ages 3. Life in Ancient Greece 4. Greek architecture and art

11. Ancient Rome 86

1. Origins, Monarchy and Republic 2. The Empire 3. Life in Ancient Rome 4. Religion, architecture and art

12. Spain in Antiquity 96

1. The Iberians and the Celts 2. The colonisers and Tartessos 3. Roman Hispania

Contents

FOTO?

3

1 Planet Earth

The Solar System

The Solar System consists of a single star, the Sun, and the planets that orbit it. There are eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. (1)

Our own planet, the Earth (2), is the fifth biggest planet in the Solar System. It has a surface area of 510 million square kilometres (km2). It is the third closest planet to the Sun, which is 150 million km away.

Most planets in the Solar System have one or more satellites. The Earth only has one satellite: the Moon.

The Earth is the only planet in the Solar System where life exists. The following conditions make this possible:• Temperature: its distance from the Sun

means that it is not too hot or too cold.• Atmosphere: it contains essential gases, like

oxygen.• Water: it is necessary for all living things.

1The Earth and its movements

• What is the solid outer layer of the Earth called?

• What is the rotation of the Earth?

• What is the result of the revolution of the Earth?

ACTIVITIES

2. THE OUTER STRUCTURE OF THE EARTH

Orbit: movement of one celestial body around another.

Satellite: celestial body that orbits a planet.

GLOSSARY

1. THE SOLAR SYSTEM

MercuryEarth

Jupiter SaturnUranus Neptune

Venus Mars

SUN

The hydrosphere is the total of all the water that exists on our planet.

The lithosphere is the Earth's solid outer layer.

The atmosphere is the layer of gases that surrounds the Earth.

4

day

North Pole

night

the Sun's rays

South Pole

axis of rotation

the Earth's tilt: 23.5° to the Sun

west to east direction

It takes 24 hours.

3. ROTATION OF THE EARTH

4. REVOLUTION OF THE EARTH

The movement of the Earth

Like other objects in the Solar System, the Earth moves all the time. It has two types of movement: rotation and revolution. (3 and 4)

• Rotation: the Earth spins continually on its own axis and takes 24 hours to complete one rotation. This is what causes day and night, since one side of the Earth's surface receives the Sun's rays and the other does not.

• Revolution: it takes the Earth 365 days to move around the Sun. This movement causes the seasons of the year, as the angle of the Sun's rays changes in each hemisphere during the year.

summer solstice

spring equinoxspring

autumn

elliptical orbit

autumn equinox

winter solstice

summer

summer

winter

winter

spring

autumn

seasons

One revolution takes 365 days.

5

Planet Earth 1

Globes and maps

The Earth is not a perfect sphere. We call this shape a geiod. We can represent it with the following tools:

• Globes are accurate representations of the Earth because they have a similar shape to our planet.

• Maps are flat representations of the Earth’s surface. Maps distort shapes, distances and surfaces. There are two main types:– Topographic maps show the main

features of the natural environment, like mountains and rivers. They also include man-made features.

– Thematic maps provide visual information on a particular subject in a specific area. They may show political, physical or human aspects.

The main features of a map

A map has the following features: a title, a scale, a key, an arrow pointing north and a grid of imaginary lines and texts.

2The representation of the Earth

Scale: ratio between the real size of the territory and the size which is shown on the map.

The scale can be indicated in two different ways:

• Numeric scale: is expressed using a fraction. The numerator represents a unit of measurement on the map, for example 1 cm. The denominator represents its distance in the real world.

1 Distance on the map

200 000 Distance in the real world

SCALE

• Graphic scale: shows the equivalent distance on a bar divided into equal segments, usually 1 cm. The figures, which are usually expressed in kilometres, indicate the actual distance that each segment represents.

0 20 40 60

SCALE

GLOSSARY

Gre

enw

ich

Mer

idia

n

180º

90º

Tropic of Cancer

Tropic of Capricorn

20º

20º

40º

60º

60º

150º

150º

120º

120º

90º 60º 30º 0º 30º 60º

60º 30º 0º 30º 60º 120º90º

120º90º

150º 180º

150º 180º

0º

20º

20º

40º

60º

40º

Equator0º

N PRECIPITATIONIN THE WORLD

0 2,700

kilometres

Scale

An arrow pointing north shows orientation.

Texts give us place names and other information.

The title tells us what the map shows.

The scale indicates how far distances have been reduced.

We use parallels and meridians to find the exact location of a place.

Over 3,000

3,000 to 1,000

1,000 to 500

500 to 250

Less than 250

Total precipitation(in mm)

The key shows the colours and symbols used on the map.

6

• What tools can we use to represent the Earth?

• What are the differences between parallels and meridians? Which lines are used to measure longitude? And latitude?

• What is the maximum value of longitude? What is the maximum value of latitude?

ACTIVITIESMeridians and parallels

Meridians and parallels form a grid of imaginary lines that help us to find the exact location of any place on Earth. (5)

• Meridians are imaginary semicircles running in a north-south direction from the North Pole to the South Pole.

• Parallels are imaginary circles running in an east-west direction.

Longitude and latitude

Longitude and latitude indicate the geographic coordinates of a place, giving its exact location on the Earth's surface.

• Longitude is the distance from a meridian to the Greenwich Meridian. – Meridians show longitude. – Its values go from 0º at the Greenwich

Meridian to 180º.

• Latitude is the distance from a parallel to the Equator. – Parallels show latitude. – Its values go from 0º at the Equator to 90º.

W E S T E R N H E M I S P H E R E

E A S T E R NH E M I S P H E R E

505399-01-20a Meridianos

Gre

enw

ich

Mer

idia

n

20º30º40º 20º 30º 40º 50º 60º50º60º 10º 0º 10º

Tropic of Capricorn

Antarctic Circle

Equator

Arctic Circle

Tropic of Cancer

505399-01-20b paralelos

90º

90º

23º 27’ N

66º 33’ N

66º 33’ S

23º 27’ S

0º

40º

60º

20º

20º

40º

60º

NOR TH E RNH EM I S P H E R E

SOU TH E RNH EM I S P H E R E

5. MERIDIANS AND PARALLELS

Longitude can be east (E) or west (W).

Latitude can be north (N) or south (S).

The prime meridian (0º) is also called the Greenwich Meridian.

The most important parallel (0º) is the Equator.

7

Planet Earth 1

1 Copy and complete the diagram.

2 Explain the meaning of these terms:

• Scale

• Key

• Solar system

3 Explain the difference between the following terms:

• The hydrosphere and the lithosphere

• Parallel and meridian

• Latitude and longitude

4 Look at the photo and describe the outer structure of the Earth.

5 Copy the illustration below in your notebook. Label the following: the Equator, Tropic of Cancer, Tropic of Capricorn, North Pole, South Pole, Greenwich meridian, northern hemisphere, southern hemisphere.

6 Are the following sentences true or false? Correct the false ones in your notebook.

a The Earth is the only planet in the Solar System where life exists.

b Rotation is what makes the Earth orbit around the Sun.

c The meridian of reference is the Equator, which divides the Earth into two hemispheres: east and west.

ACTIVITY ROUND-UP

PLANET EARTH

…

is a planet in the

…

…

…

has three characteristics that make life possible:

…

…

has an outer structure in three parts:

is

is

is

…

…

…

… …

has two types of movement:

…

…

…

is

which causes

…

…

…

is

which causes

which may be

… …

is represented by

505399-01-22 globo terráqueo

A

…

H

B

C

D

E

F

G

8

7 Copy the table below in your notebook. Complete it with the missing information.

City Latitude Longitude

Saint Petersburg 60º N 30º E

… 21º S 38º W

London … …

… 32º S 150º E

Rome … …

Quito … …

Kinshasa … …

8 Imagine that a ship is in difficulty. A rescue plane is searching for it. Look for the ship and the plane on the map above. Then copy and complete the sentences in your notebook.

The lost ship is in the … Hemisphere and its approximate coordinates are … It was going to 20º S, 120º E. Its direction should be...

The rescue plane is in the … Hemisphere, and its approximate coordinates are … Its direction will be … towards the ship.

KNOW HOW TO. How do we locate a place on a map?

We can locate a place on a map if we have its geographic coordinates: its latitude and longitude.

To do this, we need to use the parallels and meridians that were created to locate places on Earth accurately.

To calculate the geographic coordinates of a particular place, first, we find the latitude (north and south), and then the longitude (east and west). Both coordinates are measured in degrees, minutes and seconds.

Follow these steps to locate a point on a map:

1. Identify the point that you want to locate on the map.

2. Then, you need to indicate its latitude. To do this, you must first note whether it is north or south of the Equator. Then, you must locate the closest parallel to that point.

3. Next, indicate the longitude. To do this, you must first note whether you are east or west of the Greenwich Meridian. Then, locate the nearest meridian to that point.

4. The point you want to locate may not be near a parallel or a meridian. If it is between two parallels or meridians, estimate which is closer.

5. Finally, indicate the coordinates of the point which you identified.

Tropic of Cancer

Arctic Circle

Equator

Tropic of Capricorn

Antarctic Circle

150º180º 120º 90º 60º 30º 0º 30º 60º 90º 120º 150º

90º 60º 0º30º 30º 60º 90º 120º 150º

60º

40º

20º

0º

20º

40º

60º 60º

60º

40º

40º

20º

20º

0º

Saint Petersburg

Gre

enw

ich

Mer

idia

n

Kinshasa

Rio de Janeiro

Sydney

London

Quito

Rome

505399-01-21a mundi localizacion

0 2400

kilometres

Scale

Longitude is shown in numbers at the top and bottom of the map.

Latitude is shown in numbers on the left and right of the map.

GEOGRAPHY WORKSHOP

9

Planet Earth 1

2 The Earth's relief

1The Earth's crust and the Earth's relief

1

2

3

4

5

7

8

96

The structure of the Earth

The Earth has three layers:

• The crust is the Earth's Surface. It is a thin, solid layer of rock.

• The mantle is the middle layer. It is made up of various materials, including liquid rock or magma. It has two parts: the upper mantle and the lower mantle.

• The core is the deepest layer. The outer core is liquid, but the inner core is solid.

1. MAIN TYPES OF RELIEF

11

10

13

12

16

14

15

1. Mountain: high landform with steep sides.

2. Valley: area of low land between mountains.

3. Plateau: high, raised plain.

4. Plain: low, flat area of land.

5. Beach: area of sand or stones next to the sea.

6. Cliff: steep rock formation.

7. Continental shelf: underwater plateau that surrounds a continent, reaching a depth of up to 200 m.

8. Gulf: portion of the sea that is partly enclosed by land.

9. Continental slope: steep slope that leads down from the continental shelf into the deeper part of the ocean.

10. Island: area of land that is completely surrounded by water.

11. Isthmus: strip of land connecting a peninsula to a continent.

12. Abyssal plain: vast plateau that forms part of the ocean floor.

13. Peninsula: area of land that is almost entirely surrounded by water.

14. Cape: strip of land that extends into the sea.

15. Ocean trench: long, deep crack in the ocean floor.

16. Mid-ocean ridge: long mountain ridge that is found on an abyssal plain.

GLOSSARYOceans and continents

The Earth's crust consists of oceans, which cover 70% of the planet's surface, and continents, which make up the remaining 30%.

Continents are very large land masses, surrounded by oceans and seas. The six continents are Asia, America, Africa, Antarctica, Europe and Oceania.

Oceans are vast masses of salt water. The five oceans are connected to each other: the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean and the Arctic Ocean.

What is the Earth's relief?

The surface of the Earth's crust has various parts which make up the Earth's relief. It is divided into: (1)

• Continental relief.

• Coastal relief. Coasts are formed in areas where land meets seas and oceans.

• Relief on the ocean floor.

• Define: plain, valley, gulf, cape, ocean trench.

• Describe the internal structure of the Earth.

• Look at the drawing. Is the underwater relief flat? Give examples.

ACTIVITIES

The Earth's relief 2

2World relief

CONTINENT RELIEF FEATURES

America

• Mountain ranges: Rocky Mountains, Sierra Madre, and the Andes.

• Plateaus: Altiplano in Bolivia and Mato Grosso in Brazil.

• Plains: Plains of the Mississippi and Amazon rivers.

• Islands: Greenland.

• Coast: peninsulas (Labrador, Florida, Yucatán, Alaska and California).

Europe

• Mountain ranges: Caucasus, Carpathians, Alps and Pyrenees.

• Great European plain.

• Islands: Sicily, Crete, Sardinia, Balearic Islands, etc.

• Coast: peninsulas (Scandinavian, Balkan, Italian, Iberian, etc.).

Africa

• Mountain ranges: Atlas and Drakensberg mountains.

• Several plateaus.

• Islands: Madagascar.

• Coast: Somali peninsula and the Gulf of Guinea.

Asia

• The Himalayan mountain range is the highest in the world.

• Tibet is the highest plateau in the world and the Dead Sea is the deepest depression.

• Islands: numerous archipelagos (Japan, Philippines, etc) and islands (Sumatra, Borneo, etc.)

• Coast: large peninsulas (Arabic, Hindustan, Indochina, etc.) and gulfs (Persian, Bay of Bengal, etc.).

Oceania

• Mountain ranges: The Great Dividing Range.

• Several islands. Australia is the largest in the world.

Antarctica • It is mainly covered by ice.

• Look at the map:

– What is each continent's highest mountain range? What is each continent's highest peak?

– Name an island on each continent.

ACTIVITIES

Elbert4399 m

Ojos del Salado6880 m

MountWhitney4418 m

Denali6194 m

Mount Aconcagua6960 m

Orizaba5700 m

Tajamuco4217 m

Alaska Range

Chimborazo6267 m

BeaufortSea

RO

CK

Y M

OU

NT

AIN

S

BeringSea

Ber

ing

Str

ait

Yukon

Mackenzie river

Great BearLake

Great SlaveLake

GR

EA

T P

LA

I NS

Nelson river

HudsonBay

LakeWinnipeg

LakeSuperior

LakeMichigan

LakeHurón

YUCATÁNPENINSULA

Appal

ac

hian M

ountainsMissouri

Mis

siss

ippi

Mexican

plateau

Gulf ofAlaska

Cape Mendocino

Sierra Madre

LOWER CALIFORNIAPENINSULA

CapeCorrientes

Bravo

GREATBASIN

Gulf ofMexico

Cape Race

Newfoundland

Cape Hatteras

Baf�nBay

Davis

Str

ait

Cape Farewell

Greenland

SargassoSea

Cuba

LABRADORPENINSULA

Jamaica

Hispaniola

Puerto Rico

Caribbean Sea

LLANOS

Or in

oco Guiana

Highlands

Amazon

AMAZON BASIN

Mad

eira MATO

GROSSOPLATEAU

San

Fran

cisc

o

Para

náGulf ofArica

Altiplano

LakeTiticaca

AN

DE

S

GRANCHACO

THEPAMPAS

RiverPlate

PATA

GO

NIA

Stra

it of

Mag

ella

n Cape Horn

CapeSao Roque

PACIFIC

OCEAN

Drake Passage

ANTARCTICPENINSULA

POLYNESIA

FLORIDAPENINSULA

80º

60º

40º

Antarctic Circle

0º

20º

40º

60º

80º

180º 150º 120º 90º 60º

60º90º120º150º180º

Tropic of Capricorn

Equator

Tropic of Cancer

Arctic Circle

509798_01_p18_19_mundi_�sico

2. WORLD RELIEF

Major peaks

Main rivers

Lakes

2500 m

2000 m

1500 m

1000 m

400 m

200 m

0 mDepression

509798_01_p18_19_leyenda_mundi_�sico

12

K28616 m

MountCook3764 m

Teide3715

Mount Elbrus5642 m

Toubkal4165

Mount Cameroon4070 m

Mount Fuji3776 m

Ras Dashen4620 m

Mont Blanc4807 m

Puncak Jaya5030 m

Kilimanjaro5895 m

Ismoil Somoni Peak7495 m

Beluja4506 m

Sayan3492 m

Pobeda3147 mMount Narodnaya

1894 m

Mount Everest8850 m

4042 m

MountEtna3349 m3478 m

Mulhacén

Mount Tahat3003 m

Emi-koussi3415 m

Mount Kosciusko2230 m

Mount Kenya5199 m

Cathkin3660 m

Mit

um

ba

Mou

ntai

ns

Scan

dina

vian

Mounta

ins

Verkhoyansk

Yablonovy R

ange

Stanovoy Range Kolyma U

pla

nd

Altai Mountains

Tien Shan

Mountains

Kunlun Mountains Zagros Mountains

Newfoundland

Cape Farewell

Denmark Strait

Greenland

A R C T I C O C E A N

GreenlandSea

Iceland

NorwegianSea

BritishIsles North

Sea

North CapeBarents

Sea

CapeFinisterre

SCANDINAVIANPENINSULA

Baltic S

ea

A T L A N T I C

O C E A N

CapeSao Roque

CanaryIslands

Cape of Good Hope

Niger

LakeChad

DARFURPLATEAU

CENTRALPLATEAU

OF ANGOLA

Congo

Rift

Va

lle

y

ATLAS MOUNTAINS

TibestiMountains

Drakensberg

Mo

un

tain

sM

ozam

biqu

e Ch

anne

l

Madagascar

LakeMalawi

LakeTanganyika

LakeVictoria

EthiopianPlateau

SOMALIPENINSULA

LIBYANDESERT

Nile

S A H A R A

KALAHARIDESERT

Orange

IBERIANPENINSULA

PYRENEES

ALPS

Rhine

Danub eITALIANPENINSULA

Mediterranean Sea

ANATOLIANPLATEAU

GREAT EUROPEAN PLAIN

Dn

iep

er

Do

n

Volga

EASTEUROPEAN

PLAIN

UR

AL M

OU

NTA

INS

Ural

Red Sea

BlackSea

Caspian Sea

CAUCASUSMOUNTAINSEuphrates

ARABIANPENINSULA

IRANIANPLATEAU

Hindu

Kus

h

WESTSIBERIAN

PLAIN

AralSea

LakeBalkhash

Irtysh

Ob

Yenisey

TAYMIR

PENINSULA

KaraSea

East SiberiaSea

LakeBaikal

CENTRAL SIBERIANPLATEAU

GOBI DESERT

PLATEAUOF TIBETHIMALAYAS

Kolim

a

BeringSea

KAMCHATKAPENINSULA

Amur

MA

NCH

URI

A

Yello

w river

NORTH CHINAPLAIN

Yangtze

Mekong

THAR

DESERT

HINDUSTANPENINSULA

ArabianSea

INDOCHINAPENINSULA

PersianGulf

CapeVerde

Cape Guardafui

Bay ofBengal

Sumatra

Java

Borneo New Guinea

CapeComorin

Coral Sea

GR

EA

T DIV

IDIN

G R

AN

GE

South ChinaSea

Philippines

MELANESIA

MICRONESIA

KIMBERLEY

PLATEAU

GREAT SANDYDESERT

GREAT VICTORIADESERT

Dar

ling

Tasmania

Murray

North WestCape

CapeLeeuwin

GreatAustralian

Bight

New Zealand

I N D I A N

O C E A N

WeddellSea

Zambezi

S O U T H E R N O C E A N

Ganges

Indus

THE EARTH’S RELIEF

CARPATHIANMOUNTAINS

30º 0º 30º 60º 90º 120º 150º 180º

80º

60º

40º

20º

0º

20º

40º

60º

80º

180º150º120º90º60º30º0º30º

Sea ofOkhotsk

Cape Lopatka

KOREANPENINSULA

Japan

Formosa

Ahaggar Mountains

.

0 880

kilometres

Scale

509798_01_p18_19_mundi_�sico13

The Earth's relief 2

Faults and folds

According to the theory of plate tectonics, the Earth's crust is formed of tectonic plates. Each one is a few kilometres thick. They fit together like pieces of a puzzle, and are constantly moving due to the Earth's internal forces.

Sometimes this movement causes the plates to collide with each other. When this happens, one plate slides under the other, towards the Earth's interior.

As a result of the movement of the Earth's mantle, the Earth's crust is under continuous pressure near the tectonic plate boundaries. This causes faults and folds. (3 to 6)

3Relief formation

Magma: very hot material from the Earth's interior.

Tectonic plate: section of the Earth's crust which is constantly moving due to the internal forces of the Earth. A plate can be formed by land, the ocean floor, or by both.

Tsunami: series of giant waves caused by an earthquake or by a volcanic eruption on the ocean floor.

GLOSSARY

FOLDS FAULTS

• When the internal forces of the Earth's crust act on softer rocks, the Earth’s surface bends and forms folds. (3)

• When the internal forces of the Earth's crust act on rigid materials, the crust breaks and splits into blocks, called faults. (4)

• Some mountain ranges, or part of them, are formed by materials that fold. (5)

• Some blocks of land rise to form mountains and plateaus, while others sink to form valleys and plains. (6)

5. Landscape created by folds.

3. Formation of a fold. 4. Formation of a fault.

6. Landscape created by faults.

Some areas sink.The raised areas form mountains. The raised areas are

mountains.The sunken area creates a large valley.

14

• Define the following terms: fault, fold, volcano, lava. • Explain how an earthquake occurs. You can draw a diagram to help.

ACTIVITIES

The magma rises to the Earth's surface through an opening called a crater.

During an eruption, magma rises to the Earth's surface. It goes up the volcano's main channel, or vent. Magma is called lava as it leaves the volcano.

Expelled materials accumulate around the volcano and form a cone.

7. ERUPTION OF A VOLCANO

8. EARTHQUAKE

During an earthquake, energy is released in seismic waves.

The epicentre is the closest point on the Earth's surface to the hypocentre.

The point under the Earth's surface where seismic waves are released from is called the hypocentre.

Volcanoes

Volcanoes are cracks in the Earth's crust that allow materials from inside the Earth to escape, at high temperatures. (7)

These cracks are formed by two tectonic plates clashing together, or as a result of the Earth's internal forces.

Most volcanoes are found near the boundaries of tectonic plates, where the Earth's crust is weakest.

Most volcanic eruptions occur on the ocean floor.

Earthquakes

Earthquakes or tremors are violent movements of the Earth's crust. (8) The most intense earthquakes are capable of changing the Earth's relief.

They are caused by the collision of plates, the movements of faults or volcanic eruptions.

A tsunami or tidal wave is a series of giant waves, which are caused by an earthquake or a volcanic eruption on the ocean floor.

The magnitude of an earthquake is measured using a seismograph.

15

The Earth's relief 2

Changes in relief

Terrestrial relief changes over the course of time due to the actions of external forces or agents: temperature, water, wind and living things. There are three main processes: erosion, transportation and deposition.

4How does relief change?

• There is a great difference between daytime and night-time temperatures in mountains and deserts.

• Water enters the cracks in rocks and then freezes. As water expands when it freezes, the changes in temperature can break the rocks. (9)

Temperature

• Wind transports materials that collide with rocks and wear them down.

• Particles of eroded materials are deposited, forming sand dunes. (10)

Wind

• Rocks and soil are fragmented by tree roots and the tunnels that animals dig.

• Human beings make big changes to the Earth's landscape: the construction of buildings, tunnels, the expansion of farmland, etc. (12)

Living things

AGENTS THAT MODIFY RELIEF

11. The Grand Canyon (USA). 9. La Pedriza, Sierra de Guadarrama (Spain).

12. Motorway (Galicia, Spain).10. Desert (Libya).

• Water dissolves rocks, creating caves.

• Rivers modify relief along their whole path: in the upper slopes, they erode materials forming canyons and valleys; they transport eroded material along their middle course; and they deposit sediments in low areas. (11)

• Waves and currents form cliffs (erosion) and beaches (deposition).

Water

16